Phosphorochloridates esters

Comins, D.L., Jacobine, A.E. Marshall, J.A., and Turnbull, M.M., Phosphonate ester preparation from active methylene compounds and phosphorochloridate esters, Synthesix, 309, 1978. 

Acylation of 3,5-diamino-1,2,4-thiadiazole by ethyl chloroformate yields the 3,5-bis(ethoxycarbonylamino) derivative.67 Phosphorochloridic esters [(RO)2POCl] attack the 3-position preferentially, producing the phosphor-amidic esters (509).390 The action of diphenylphosphinothioic chloride (Ph2PSCl) (see Section IV,C) on Hector s base in pyridine yields a monoacyl derivative, substitution occurring probably at the exocyclic imino group.391 Methylation of 3,5-bisanilino-l,2,4-thiadiazole with sodium hydride-methyl iodide in dimethylformamide produces the mono and dimethyl derivatives, of structures 510 and 511, as shown by 15N and 13C NMR spectroscopy.31... 

Esters of pyrophosphorous add can be prepared by using sodium dialkyl phosphite and a dialkyl phosphorochloridite (5.321). If a phosphorochloridate ester is used, an ester of hypophosphoric acid is obtained (5.322). 

Diethyl chlorophosphate Phosphorochloridic acid, diethyl ester (3,9) (814-49-3)... 

Diphenyl phosphorochloridate Diphenyl chlorophosphate Phosphorochloridic acid, diphenyl ester (8,9) (2524-64-3)... 

The alcoholysis of the cyclic phosphate of catechol by alditols can lead, after acid hydrolysis of intermediate, cyclic phosphates, to the selective formation of phosphoric esters of the primary hydroxyl groups in the alditols. Thus, erythritol and D-mannitol afford, after chromatographic purification of the reaction products, their 1-phosphates in yields of 31 and 38%, respectively.217 The method was used to convert riboflavine into riboflavine 5 -phosphate.218 1-Deoxy-1-fluoro-L-glycerol has been converted into the 3-(dibenzyl phosphate) in 54% yield by selective reaction with dibenzyl phosphorochloridate. 219... 

Trialkyl phosphites undergo reaction with molecular halogen via a mechanism reminiscent of the Michaelis-Arbuzov reaction to form the dialkyl phosphorochloridate in good yield (Equation 4.4).7 With cyclic esters, the halogen performing the displacement reaction at carbon remains attached within the molecule. 

The ester/alkyne rearrangement system can be extended by conjugation to involve a more distant site. The reaction of diethyl phosphorochloridate with 3-methylhex-4-yne-2-ene-l-ol leads to the vinylogous propargylic ester rearrangement as shown in Equation 4.39.176... 

Dimethyl and diethyl phosphorofluoridate were hydrolysed much more quickly, the order being Me>Et>Pr complete hydrolysis of the ethyl ester took about 4 hr. Small quantities of the di-isopropyl, but not the diethyl ester, could be steam-distilled. Bi-isopropyl phosphorochloridate can be readily identified by allowing it to react with aniline to give the crystalline phenylphosphoramidate ... 

On pp. 45 and 57 we referred to the action of chlorine1 and of N-chlorosuccinimide2 on dialkyl phosphites producing dialkyl phosphorochloridates. We have made use of the latter in producing a variety of esters of orthophosphoric acid and of phos-phoramidates, and reference has already been made to many such reactions (p. 82). These processes are, in a sense, phosphorylations of the alcohols or of the amines respectively. 

Toy2 prepared this ester3 (as well as related esters) by the controlled hydrolysis of 2 mol. of diethyl phosphorochloridate ... 

The ester must in addition contain some group which will initiate the approach of the ester to the surface of the enzyme. In this connexion it should be noted that di-isopropyl phos-phorochloridate (III, X = Cl), in which the chlorine atom is chemically very reactive,3 has no toxic properties, is devoid of myotic and anti-cholinesterase activity. In this compound, the chlorine is hydrolysed very quickly in water and would probably be destroyed extremely quickly in vivo. We have shown, quite conclusively, that in non-polar solvents the phosphorochloridate... 

Diethyl chlorophosphate Phosphorochloridic acid, diethyl ester (8,9) (814-49-3) Isoamyl nitrite Nitrous acid, isopentyl ester (8) Nitrous acid, 3-methylbutyl ester (9) (110-46-3)... 

Phosphate groups can also be removed by dissolving-metal reduction. Reductive removal of vinyl phosphate groups is one of the better methods for conversion of a carbonyl compound to an alkene.150 151 The required vinyl phosphate esters are obtained by phosphorylation of the enolate with diethyl phosphorochloridate or NJ, N, N -tetra-methyldiamidophosphorochloridate.152 153... 

In preparation for the eventual removal of the undesired oxygen function at C-10 of 313 via a Birch reduction, the phenol 313 was phosphorylated with diethyl phosphorochloridate in the presence of triethylamine to give 314, which underwent stereoselective reduction with sodium borohydride with concomitant N-deacylation to deliver the amino alcohol 315. N-Methylation of 315 by the Eschweiler-Clarke protocol using formaldehyde and formic acid followed by ammonolysis of the ester group and acetylation of the C-2 hydroxyl function afforded 316. Dehydration of the amide moiety in 316 with phosphorus oxychloride and subsequent reaction of the resulting amino nitrile 317 with LiAlH4 furnished 318, which underwent reduction with sodium in liquid ammonia to provide unnatural (+)-galanthamine. 

---